Question

我发了一篇原帖here

起初，我试图填写CGPoint ** allPaths。

第一维是“路径”，第二维是“路点”。而且我得到了一个CGPoint。

例如：allPaths [0] [2]会给我第一条路径的CGPoint，第三条路点。

我在简单的C中成功地做了令人讨厌的循环。现在我试图在Obj-C中用NSMutableArrays做同样的事情。

这是我的代码：

CCTMXObjectGroup *path;
NSMutableDictionary *waypoint;

int pathCounter = 0;
int waypointCounter = 0;

NSMutableArray *allPaths = [[NSMutableArray alloc] init];
NSMutableArray *allWaypointsForAPath = [[NSMutableArray alloc] init];

//Get all the Paths
while ((path = [self.tileMap objectGroupNamed:[NSString stringWithFormat:@"Path%d", pathCounter]]))
{
    waypointCounter = 0;
    //Empty all the data of the waypoints (so I can reuse it)
    [allWaypointsForAPath removeAllObjects];

    //Get all the waypoints from the path
    while ((waypoint = [path objectNamed:[NSString stringWithFormat:@"Wpt%d", waypointCounter]]))
    {
        int x = [[waypoint valueForKey:@"x"] intValue];
        int y = [[waypoint valueForKey:@"y"] intValue];

        [allWaypointsForAPath addObject:[NSValue valueWithCGPoint:CGPointMake(x, y)]];
        //Get to the next waypoint
        waypointCounter++;
    }

    //Add the waypoints of the path to the list of paths
    [allPaths addObject:allWaypointsForAPath];

    //Get to the next path
    pathCounter++;
}

我的实际问题是allPaths中的所有路径都等于最后一个路径。（所有第一条路径都被最后一条路径覆盖）

我知道这是因为这行[allPaths addObject：allWaypointsForAPath]。

然而，我应该怎么做？

Answer 1

哦，我觉得我发现了什么！不确定内存问题，但我想垃圾收集器应该可以工作吗？

实际上，我只需要像这样在循环中声明NSMutableArray * allWaypointsForAPath：

int pathCounter = 0;
int waypointCounter = 0;

NSMutableArray *allPaths = [[NSMutableArray alloc] init];

//Get all the PathZ
while ((path = [self.tileMap objectGroupNamed:[NSString stringWithFormat:@"Path%d", pathCounter]]))
{
    waypointCounter = 0;
    NSMutableArray *allWaypointsForAPath = [[NSMutableArray alloc] init];
    //Get all the waypoints from the path
    while ((waypoint = [path objectNamed:[NSString stringWithFormat:@"Wpt%d", waypointCounter]]))
    {
        int x = [[waypoint valueForKey:@"x"] intValue];
        int y = [[waypoint valueForKey:@"y"] intValue];
        [allWaypointsForAPath addObject:[NSValue valueWithCGPoint:CGPointMake(x, y)]];
        //Get to the next waypoint
        waypointCounter++;
    }

    [allPaths addObject:allWaypointsForAPath];
    //Get to the next path
    pathCounter++;
}

如何动态创建带循环的2d NSMutableArray

1 个答案: